


JS simply implements multi-level Select linkage menu effect code_javascript skills
The example in this article describes the simple implementation of multi-level Select linkage menu effect code using JS. Share it with everyone for your reference. The details are as follows:
JS linkage menu, simple code to implement JS multi-level Select linkage menu, which is a menu commonly used by everyone, the menu in Select linkage state, an effect often seen on web pages, I hope everyone can use it.
The screenshot of the running effect is as follows:
The online demo address is as follows:
http://demo.jb51.net/js/2015/js-simple-select-ld-menu-codes/
The specific code is as follows:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <html> <head> <title>JS联动下拉框</title> <script language="javascript" > /* ** ==================================== ** 类名:CLASS_LIANDONG_YAO ** 功能:多级连动菜单 ** 作者:YAODAYIZI **/ function CLASS_LIANDONG_YAO(array) { //数组,联动的数据源 this.array=array; this.indexName=''; this.obj=''; //设置子SELECT // 参数:当前onchange的SELECT ID,要设置的SELECT ID this.subSelectChange=function(selectName1,selectName2) { //try //{ var obj1=document.all[selectName1]; var obj2=document.all[selectName2]; var objName=this.toString(); var me=this; obj1.onchange=function() { me.optionChange(this.options[this.selectedIndex].value,obj2.id) } } //设置第一个SELECT // 参数:indexName指选中项,selectName指select的ID this.firstSelectChange=function(indexName,selectName) { this.obj=document.all[selectName]; this.indexName=indexName; this.optionChange(this.indexName,this.obj.id) } // indexName指选中项,selectName指select的ID this.optionChange=function (indexName,selectName) { var obj1=document.all[selectName]; var me=this; obj1.length=0; obj1.options[0]=new Option("请选择",''); for(var i=0;i<this.array.length;i++) { if(this.array[i][1]==indexName) { //alert(this.array[i][1]+" "+indexName); obj1.options[obj1.length]=new Option(this.array[i][2],this.array[i][0]); } } } } </script> </head> <body> <form name="form1" method="post"> <SELECT ID="s1" NAME="s1" > <OPTION selected></OPTION> </SELECT> <SELECT ID="s2" NAME="s2" > <OPTION selected></OPTION> </SELECT> <SELECT ID="s3" NAME="s3"> <OPTION selected></OPTION> </SELECT> <br> <br><br> <SELECT ID="x1" NAME="x1" > <OPTION selected></OPTION> </SELECT> <SELECT ID="x2" NAME="x2" > <OPTION selected></OPTION> </SELECT> <SELECT ID="x3" NAME="x3"> <OPTION selected></OPTION> </SELECT> <SELECT ID="x4" NAME="x4"> <OPTION selected></OPTION> </SELECT> <SELECT ID="x5" NAME="x5"> <OPTION selected></OPTION> </SELECT> </form> </body> <script language="javascript"> //例子1------------------------------------------------------------- //数据源 var array=new Array(); array[0]=new Array("华南地区","根目录","华南地区"); //数据格式 ID,父级ID,名称 array[1]=new Array("华北地区","根目录","华北地区"); array[2]=new Array("上海","华南地区","上海"); array[3]=new Array("广东","华南地区","广东"); array[4]=new Array("徐家汇","上海","徐家汇"); array[5]=new Array("普托","上海","普托"); array[6]=new Array("广州","广东","广州"); array[7]=new Array("湛江","广东","湛江"); //-------------------------------------------- //这是调用代码 var liandong=new CLASS_LIANDONG_YAO(array) //设置数据源 liandong.firstSelectChange("根目录","s1"); //设置第一个选择框 liandong.subSelectChange("s1","s2"); //设置子级选择框 liandong.subSelectChange("s2","s3"); //例子2------------------------------------------------------------- //数据源 var array2=new Array();//数据格式 ID,父级ID,名称 array2[0]=new Array("测试测试","根目录","测试测试"); array2[1]=new Array("华北地区","根目录","华北地区"); array2[2]=new Array("上海","测试测试","上海"); array2[3]=new Array("广东","测试测试","广东"); array2[4]=new Array("徐家汇","上海","徐家汇"); array2[5]=new Array("普托","上海","普托"); array2[6]=new Array("广州","广东","广州"); array2[7]=new Array("湛江","广东","湛江"); array2[8]=new Array("不知道","湛江","不知道"); array2[9]=new Array("5555","湛江","555"); array2[10]=new Array("++++","不知道","++++"); array2[11]=new Array("111","徐家汇","111"); array2[12]=new Array("222","111","222"); array2[13]=new Array("333","222","333"); //-------------------------------------------- //这是调用代码 //设置数据源 var liandong2=new CLASS_LIANDONG_YAO(array2); //设置第一个选择框 liandong2.firstSelectChange("根目录","x1"); //设置子选择框 liandong2.subSelectChange("x1","x2") liandong2.subSelectChange("x2","x3") liandong2.subSelectChange("x3","x4") liandong2.subSelectChange("x4","x5") </script> </html>
I hope this article will be helpful to everyone’s JavaScript programming.

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